12.7 mm机枪枪管损伤演变规律及其与椭圆弹孔关系

为探明12.7 mm大口径机枪枪管损伤演变规律及其对椭圆弹孔的影响,开展了寿命射击试验研究.采用光学显微镜、扫描电子显微镜、内窥镜和口径量规对枪管进行观察和测量,得到枪管内膛在寿命周期内的损伤规律.结果表明:12.7 mm机枪枪管损伤存在3个典型区域,分别是线膛起始部位、高膛压区部位、枪管口部;这3个区域损伤速率和方式...

The Evolution of Gun Barrel Damage and Its Relation with Elliptic Hole

The life firing experiment was carried out to investigate the damage evolution law of 12.7 mm large caliber machine gun barrel and its influence on elliptic hole. Optical microscope, scanning electron microscope, endoscope and caliber gauge were used to observe and measure the damaged barrel, and the damage rule of barrel bore during its life cycle was obtained. The results show that three typical barrel damage regions of 12.7 mm machine gun are at the initial position of refiled bore, the high bore pressure zone and the muzzle of barrel. The damage rates and modes are different in these three regions. The Cr layer in the initial region of refiled bore has a high shedding rate, leading to a high expansion rate of the inner diameter. In the early stage of the high bore pressure zone, the Cr layer remains intact, but in the later stage of life, the Cr layer falls off faster. The Cr layer at the muzzle of barrel is almost not shed, and the damage is mainly caused by wear. The barrel life of machine gun ends in the way of keyhole of bullet exceeding the standard. The forming reason of keyhole of bullet is that the refiling lands are damaged and stripped, which weakens the driving ability of refiling and makes the warhead rotate at a low speed, thus leading to the keyholes of bullet.